Forward Secant Swirl Tube

ABSTRACT

A forward secant swirl tube may be used to separate heavier particles such as oil and moisture from an air flow. The swirl tube includes a central hub having a centerline and a circular perimeter. An outer circular housing extends from an inlet edge to an outlet edge. A plurality of vanes extends from the central hub to the outer housing. The vanes are equally spaced around the central hub. Each vane has an inlet transition portion connected to a discharge portion. The top edge of the inlet transition portion of each vane is offset from the centerline of the central hub forming a forward secant line with respect to the centerline of the central hub and a direction of spin induced by the plurality of vanes.

BACKGROUND Field of the Disclosure

The embodiments described herein relate to apparatuses, systems, andmethods for a forward secant swirl tube.

Description of the Related Art

Swirl tubes, also referred to as inline non-reversing cyclones,typically include a plurality of vanes within a tube that are configuredto cause the airflow through the tube to rotate or swirl. The designuses the principles of centripetal acceleration to arrange the particlesby mass flow annularly for separation purposes. One of the obstacles forusing a swirl tube is the cost of fabrication due to the geometry of thevanes at the inlet of the swirl tube. Recent advances in 3D printing hasovercome some of the manufacturing issues. However, 3D printing is notapplicable or cost effective for all industries, such as applicationsthat involve high temperatures and/or sanitary applications. Forexample, in some food applications the swirl tube may be subjected tocaustic solutions at near boiling temperatures, or hot cooking oil.Plastic 3D printed swirl tubes may not be suitable for suchapplications. High temperature applications typically require swirltubes made out of metal, which may be cost prohibitive for 3D printingmanufacturing.

Swirl tubes are generally preferred for their relative simplicity. Oftenthe leading edge of the vanes within the swirl tube are aligned with thecenterline of the central hub of the swirl tube. With certain fluidloading situations, a longer transition section is needed at the outsideedge for a reduction in pressure drop. These swirl tubes are calledbackward secant swirl tubes as the leading edges of the vanes contactthe inner and outer walls at a secant of each behind the normal tangentin reference to the direction of spin induced by the vanes. Thisgeometry of backward secant swirl tubes poses an even larger headachefor fabrication, due to an even more advanced geometry used in thetransition section. Other disadvantages may exist.

SUMMARY

The present disclosure is directed to apparatus, systems, and methodsfor a swirl tube that overcomes at least one of the disadvantagesdiscussed above. The present disclosure is directed to apparatuses,systems, and methods for a forward secant swirl tube.

An embodiment of the present disclosure is an apparatus comprising acentral hub having a centerline and a circular perimeter. The apparatusincludes an outer housing, the outer housing comprising a circular wallthat extends from an inlet edge to an outlet edge. The apparatusincludes a plurality of vanes that extend from the central hub to theouter housing, the plurality of vanes equally spaced around the circularperimeter of the central hub, each vane of the plurality of vanes havingan inlet transition portion connected to a discharge portion, the inlettransition portion having a top edge and the discharge portion having abottom edge. The top edge of the inlet transition portion of each vaneof the plurality of vanes is offset from the centerline of the centralhub and the top edge forms a forward secant line with respect to thecenterline of the central hub and a direction of spin induced by theplurality of vanes.

The apparatus may include five vanes. The apparatus may include sixvanes. The discharge portion of each vane of the plurality of vanes mayhave a constant incline along a line normal to the centerline of thecentral hub. The inlet transition portion of each vane of the pluralityof vanes may include an upper portion, a middle portion, a lowerportion, a first bend at a first interface between the upper portion andthe middle portion, and a final bend at a second interface between themiddle portion and the lower portion, wherein the lower portion of theinlet transition portion is connected to the discharge portion.

The upper portion, middle portion, and lower portion of each vane of theplurality of vanes may comprise a face. The face of the upper portion ofthe inlet transition portion of each vane of the plurality of vanes maybe oriented at a first angle with respect to a plane along the outletedge of the outer housing. The face of the middle portion of the inlettransition portion of each vane of the plurality of vanes may beoriented at a second angle with respect to the plane along the outletedge of the outer housing. The face of the upper portion of the inlettransition portion of each vane of the plurality of vanes may beoriented at a final angle with respect to the plane along the outletedge of the outer housing. The first angle may be greater than thesecond angle and the second angle may be greater than the final angle.

The apparatus may be comprised of stainless steel. A direction of flowthrough the plurality of vanes may be upwards with respect to gravity.The central hub may include a top surface. The top surface may include afirst face, a second face, and an interface between the first face andthe second face. The first face may extend downward toward the pluralityof vanes from the interface and the second face may extend downwardtoward the plurality of vanes from the interface.

An embodiment of the present disclosure is a system comprising a flowtube having an outer housing, an inlet, and an outlet. The systemincludes an inner housing positioned within the outer housing of theflow tube. The system includes a collection housing having an innerchamber and at least one opening between the inner housing and the outerhousing, the at least one opening in communication with the innerchamber of the collection housing. The system includes a swirl tubepositioned between the inlet and the outlet of the flow tube, whereinfluid flowing through the inlet of the flow tube passes through theswirl tube.

The swirl tube comprises a central hub having a centerline and acircular perimeter. The swirl tube includes an outer housing, the outerhousing comprising a circular wall that extends from an inlet edge to anoutlet edge. The swirl tube includes a plurality of vanes that extendfrom the central hub to the outer housing, the plurality of vanesequally spaced around the circular perimeter of the central hub. Eachvane of the plurality of vanes having an inlet transition portionconnected to a discharge portion, the inlet transition portion having atop edge and the discharge portion having a bottom edge, wherein the topedge of the inlet transition portion of each vane of the plurality ofvanes is offset from the centerline of the central hub and the top edgeforms a forward secant line with respect to the centerline of thecentral hub and a direction of spin induced by the plurality of vanes.Wherein the swirl tube causes heavier particles of the fluid flowingthrough the swirl tube to flow into the inner chamber of the collectionhousing via the at least one opening and the remaining fluid flowing outthe outlet of the flow tube.

The heavier particles may be at least one of moisture droplet, oildroplets, and vapor. The discharge portion of each vane of the pluralityof vanes may have a constant incline along a line normal to thecenterline of the central hub. The inlet transition portion of each vaneof the plurality of vanes may comprise an upper portion, a middleportion, a lower portion, a first bend at a first interface between theupper portion and the middle portion, and a final bend at a secondinterface between the middle portion and the lower portion, wherein thelower portion of the inlet transition portion is connected to thedischarge portion.

The upper portion, middle portion, and lower portion of each vane of theplurality of vanes may comprise a face. The face of the upper portion ofthe inlet transition portion of each vane of the plurality of vanes maybe oriented at a first angle with respect to a plane along the outletedge of the outer housing. The face of the middle portion of the inlettransition portion of each vane of the plurality of vanes may beoriented at a second angle with respect to the plane along the outletedge of the outer housing. The face of the lower portion of the inlettransition portion of each vane of the plurality of vanes may beoriented at a final angle with respect to the plane along the outletedge of the outer housing. The first angle may be greater than thesecond angle and the second angle may be greater than the final angle.The plurality of vanes may comprise five vanes and the outer housing mayhave an inner diameter of 12 inches. The plurality of vanes may comprisesix vanes and the outer housing may have an inner diameter of 24 inches.

An embodiment of the present disclosure is a method that comprisesproviding a flow of fluid through a forward secant swirl tube. Themethod includes moving heavier particles within the flow toward an outerdiameter of the forward secant swirl tube via centripetal acceleration.The method includes removing at least a portion of the heavier particlesfrom the flow of fluid and discharging the flow of fluid from theforward secant swirl tube.

The heavier particles may be moisture particles and oil particles. Theforward secant swirl tube may comprise a central hub having a centerlineand a circular perimeter. The forward secant swirl tube may include anouter housing, the outer housing comprising a circular wall that extendsfrom an inlet edge to an outlet edge. The forward secant swirl tube mayinclude a plurality of vanes that extend from the central hub to theouter housing, the plurality of vanes equally spaced around the circularperimeter of the central hub, each vane of the plurality of vanes havingan inlet transition portion connected to a discharge portion, the inlettransition portion having a top edge and the discharge portion having abottom edge.

The top edge of the inlet transition portion of each vane of theplurality of vanes is offset from the centerline of the central hub andthe top edge may form a forward secant line with respect to thecenterline of the central hub and a direction of spin induced by theplurality of vanes. The inlet transition portion of each vane of theplurality of vanes may include a plurality of faces formed by a pressbrake.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of an embodiment of a swirl tube.

FIG. 2 shows an inlet view of the swirl tube of FIG. 1.

FIG. 3 shows a cross-section view of the swirl tube of FIG. 1 with theouter housing removed for clarity.

FIG. 4 shows a perspective view of the swirl tube of FIG. 1 with theouter housing removed for clarity.

FIG. 5 shows a side view of the swirl tube of FIG. 1 with the outerhousing removed for clarity.

FIG. 6 shows a perspective view of an embodiment of a swirl tube.

FIG. 7 shows an inlet view of the swirl tube of FIG. 6.

FIG. 8 shows a perspective view of the swirl tube of FIG. 6 with theouter housing removed for clarity.

FIG. 9 shows a side view of the swirl tube of FIG. 6 with the outerhousing removed for clarity.

FIG. 10 shows a perspective view of an embodiment of a system thatutilizes a swirl tube.

FIG. 11 shows a cross-section view of an embodiment of the system ofFIG. 10 that utilizes a swirl tube.

FIG. 12 shows a bottom perspective view of the embodiment of the systemof FIG. 10 that utilizes a swirl tube.

FIG. 13 is a flow chart of an embodiment of a method of the disclosure.

While the disclosure is susceptible to various modifications andalternative forms, specific embodiments have been shown by way ofexample in the drawings and will be described in detail herein. However,it should be understood that the disclosure is not intended to belimited to the particular forms disclosed. Rather, the intention is tocover all modifications, equivalents and alternatives falling within thescope of the invention as defined by the appended claims.

DETAILED DESCRIPTION

FIG. 1 shows a perspective view of an embodiment of a swirl tube 100.The swirl tube 100 include a central hub 120, and outer housing 110, andfive vanes 130 that extend between the central hub 120 and the outerhousing 110. The outer housing 110 is a circular wall that extends froman inlet edge 113 to an outlet edge 114. The outer housing 110 has aninner surface 111 and an outer surface 112. The swirl tube 100 may havean inner diameter of twelve (12) inches. However, the inner diameter ofthe swirl tube 100 is not limited to twelve (12) inches and may bevaried depending on the application. For example, in some applicationsthe inner diameter may be thirty (30) inches.

The central hub 120 has a circular perimeter 125 (best shown in FIG. 2)with the vanes 130 equally spaced around the perimeter 125. The topportion of the central hub 120 includes a first face 121 and a secondface 122 with a bend 123 between the first and second faces 121, 122.The purpose of the angled faces is to allow for drainage for sanitarypurposes. The central hub 120 has a centerline 124. This centerline 124is shared with the outer housing 110. The top portion of the central hub120 is configured to be more aerodynamic that as flat faced top. Theconfiguration of the top portion of the central hub 120 is shown forillustrative purposes and may be varied depending on the application aswould be appreciated by one of ordinary skill in the art having thebenefit of this disclosure.

The vanes 130 are configured to cause airflow through the vanes 130 toswirl allowing centripetal acceleration to remove heavier particles,such as water and oil droplets and/or vapor, from the air flow. The vane130 includes inlet transition portion 140 connected to a dischargeportion 150. The inlet transition portion 140 includes a top edge 146 ofthe vane 130 and the discharge portion 150 includes a bottom edge 151 ofthe vane 130. The top edge 146 of each vane 130 is offset from thecenterline 124 of the central hub 120. Specifically, the vanes 130 areconfigured so that the top edge 146 forms a forward secant line withrespect to the centerline 124 of the central hub 120 and a direction ofspin (indicated by arrows 1) induced by the plurality of vanes 130.

The inlet portion 140 include an upper portion 141, a middle portion143, a lower portion 145, a first bend 142 at a first interface betweenthe upper portion 141 and the middle portion 143, and a final bend 144at a second interface between the middle portion 143 and the lowerportion 145 with the lower portion 145 of the inlet transition portion140 being connected to the discharge portion 150. In one embodiment, themiddle portion 143 may consist of multiple bends. Specifically, theupper portion 141, middle portion 143, and lower portion 145 of eachvane 130 may comprise a face that extends from the central hub 120 tothe outer housing 110. The face of the upper portion 141 of the inlettransition portion 140 of each vane is oriented at a first angle withrespect to a plane along the outlet edge 114 of the outer housing 110.The face of the middle portion 143 of the inlet transition portion 140of each vane is oriented at a second angle with respect to the planealong the outlet edge 114 of the outer housing 110. The face of thelower portion 145 of the inlet transition portion 140 of each vane isoriented at a final angle with respect to the plane along the outletedge 114 of the outer housing 110. The first angle is greater than thesecond angle and the second angle is greater than the final angle. Theinlet transition portion 140 allows the discharge portion 150 of thevanes 130 to have a constant incline or straight section. The geometryof the discharge portion 150 may be formed by simply stamping sheetmetal using an auger flight press. The different portions 141, 143, 145of the inlet transition portion 140 may be formed with a press brake.These portions could take on a different number and angles may be varieddepending on the application as would be appreciated by one of ordinaryskill in the art having the benefit of this disclosure.

FIG. 2 shows a front view of the swirl tube 100. As shown, the vanes 130are equally spaced around the perimeter 125 of the central hub 120. Thetop edge 146 of each vane 130 is offset from the center of the swirltube 100, which is the centerline 124 of the central hub 120.Specifically, the vanes 130 are configured so that the top edge 146forms a forward secant line with respect to the centerline 124 of thecentral hub 120 and a direction of spin induced by the plurality ofvanes 130. A fluid flow would enter the swirl tube 100 having a highaxial velocity and the vanes 130 direct the airflow to have a highradial velocity with respect to the swirl tube 100.

FIG. 3 shows a cross-section view of the swirl tube 100 with the outerhousing 110 removed for clarity. As shown in FIG. 3, the dischargeportion 150 of the vanes 130 is forms substantially a straight line fromthe central hub 120 to the outer housing 110 (not shown). Thus, theinner fluid flowing through the swirl tube 100 (i.e. the fluid adjacentto the central hub 120) has to travel approximately the same distance asthe outer fluid flowing through the swirl tube 100 (i.e. the fluidadjacent to the outer housing 110) to transition to its swirl flow. FIG.4 shows an isometric view of the swirl tube 100 with the outer housing110 removed for clarity. FIG. 5 shows a side view of the swirl tube 100with the outer housing 110 removed for clarity.

The performance of a swirl tube 100 having a forward secant designdiffers to the performance of a swirl tube with the vanes aligned withthe center point of the swirl tube and swirl tubes that have the vanesin a backward secant configuration. One reason for the difference inperformance is due to the inlet geometry of the forward secant swirltube 100 no longer changes with respect to the distance from thecenterline 124 of the swirl tube 100. Thus, the fluids near the centerof the swirl tube 100 have to travel approximately the same distance totransition from the axial flow to the swirl flow as do the fluids nearthe outer housing 110. This results in an increased pressure drop ofapproximately 30%, which may not be suitable for some applications.While the forward secant design of the swirl tube 100 results in anincreased pressure drop, the transition to swirl flow may beaccomplished in a shorter axial distance than prior swirl tubes, whichmay be beneficial in some applications where space is at a premium.

FIG. 6 shows a perspective view of an embodiment of a swirl tube 200.The swirl tube 200 include a central hub 220, and outer housing 210, andsix vanes 230 that extend between the central hub 220 and the outerhousing 210. The outer housing 210 is a circular wall that extends froman inlet edge 213 to an outlet edge 214. The outer housing 210 has aninner surface 211 and an outer surface 212. The swirl tube 200 may havean inner diameter of twenty-four (24) inches.

The central hub 220 has a circular perimeter 225 (best shown in FIG. 7)with the vanes 230 equally spaced around the perimeter 225. The topportion of the central hub 220 includes a first face 221 and a secondface 222 with a bend 223 between the first and second faces 221, 222.The central hub 220 has a centerline 224, which is the center point ofthe swirl tube 200. The top portion of the central hub 220 is configuredto be more aerodynamic that as flat faced top. The configuration of thetop portion of the central hub 220 is shown for illustrative purposesand may be varied depending on the application as would be appreciatedby one of ordinary skill in the art having the benefit of thisdisclosure.

The vanes 230 are configured to cause airflow through the vanes 230 toswirl to use centripetal acceleration to remove heavier particles, suchas water and oil droplets and vapor, from the air flow. The vanes 230includes inlet transition portion 240 connected to a discharge portion250. The inlet transition portion 240 includes a top edge 246 of thevane 230 and the discharge portion 250 includes a bottom edge 251 of thevane 230. The top edge 246 of each vane 230 is offset from thecenterline 224 of the central hub 220. Specifically, the vanes 230 areconfigured so that the top edge 246 forms a forward secant line withrespect to the centerline 224 of the central hub 220 and a direction ofspin (indicated by arrows 1) induced by the plurality of vanes 230.

The inlet portion 240 includes an upper portion 241, a middle portion243, a lower portion 245, a first bend 242 at a first interface betweenthe upper portion 241 and the middle portion 243, and a final bend 244at a second interface between the middle portion 243 and the lowerportion 245 with the lower portion 245 of the inlet transition portion240 being connected to the discharge portion 250. Specifically, theupper portion 241, middle portion 243, and lower portion 245 of eachvane 230 may comprise a face that extends from the central hub 220 tothe outer housing 210. The face of the upper portion 241 of the inlettransition portion 240 of each vane is oriented at a first angle withrespect to a plane along the outlet edge 214 of the outer housing 210.The face of the middle portion 243 of the inlet transition portion 240of each vane is oriented at a second angle with respect to the planealong the outlet edge 214 of the outer housing 210. The face of thelower portion 245 of the inlet transition portion 240 of each vane isoriented at a final angle with respect to the plane along the outletedge 214 of the outer housing 210. The first angle is greater than thesecond angle and the second angle is greater than the final angle. Theinlet transition portion 240 allows the discharge portion 250 of thevanes 230 to have a constant incline or straight section. The geometryof the discharge portion 250 may be formed by simply stamping sheetmetal using an auger flight press. The different portions 241, 243, 245of the inlet transition portion 240 may be formed with a press brake.These portions could take on a different number and angles may be varieddepending on the application as would be appreciated by one of ordinaryskill in the art having the benefit of this disclosure

FIG. 7 shows a front view of the swirl tube 200. As shown, the vanes 230are equally spaced around the perimeter 225 of the central hub 220. Thetop edge 246 of each vane 230 is offset from the center of the swirltube 200, which is the centerline 224 of the central hub 220.Specifically, the vanes 230 are configured so that the top edge 246forms a forward secant line with respect to the centerline 224 of thecentral hub 220 and a direction of spin induced by the plurality ofvanes 230. As flow of fluid enters the swirl tube 200 having a highaxial velocity, the vanes 230 direct the airflow to have a high radialvelocity with respect to the swirl tube 200.

FIG. 8 shows an isometric view of the swirl tube 200 with the outerhousing 210 removed for clarity. FIG. 9 shows a side view of the swirltube 200 with the outer housing 210 removed for clarity.

As discussed herein, the performance of a swirl tube 200 having aforward secant design differs to the performance of a swirl tube withthe vanes aligned with the center point of the swirl tube and swirltubes that have the vanes in a backward secant configuration. One reasonfor the difference in performance is due to the inlet geometry of theforward secant swirl tube 200 no longer changes with respect to thedistance from the centerline 224 of the swirl tube 200. Thus, the fluidsnear the center of the swirl tube 200 have to travel approximately thesame distance to transition from the axial flow to the swirl flow as dothe fluids near the outer housing 210. This results in an increasedpressure drop of approximately 30%, which may not be suitable for someapplications. While the forward secant design of the swirl tube 200results in an increased pressure drop, the transition to swirl flow maybe accomplished in a shorter axial distance than prior swirl tubes,which may be beneficial in some applications where space is at apremium.

FIG. 10 shows a perspective view of a system 500 that utilizes a swirltube 100 (best shown in FIGS. 11 and 12). FIG. 11 shows a cross-sectionview of the system 500 and FIG. 12 shows a rear perspective view of thesystem 500. The swirl tube 200 of FIGS. 6-9 may be used in a similarsystem as would be appreciated by one of ordinary skill in the arthaving the benefit of this disclosure. A gas or air flow enters a flowtube 510 of the system 500 as indicated by arrow 501. A swirl tube 100is positioned within the flow tube 510. The swirl tube 100 causes theair flow to swirl within the flow tube 510 as discussed herein. Theswirling of the air flow causes the heavy particles (e.g., water and/oroil droplets) within the air flow to move towards that outer diameter ofthe air flow. A collection housing 520 is connected to the flow tube510. The collection housing 520 includes an inner chamber 521 as shownin FIG. 11.

As shown in FIG. 11, the flow tube 510 includes an outer housing 511 andan upper inner housing 512. The outer diameter of the inner housing 512is smaller than the inner diameter of the outer housing creatingopenings 513. The openings 513 open into the inner chamber 521 of thecollection housing 520. As air travels from inlet 514 into the flow tube510 it swirls, as shown by curved arrow 504. As the air flow reaches theinner housing 512, the outer portion of the air flow enters the innerchamber 521 of the collection housing 520 as indicated by arrows 503with the central portion of the air flow flowing out through the innerhousing 512 as indicated by arrow 502.

As discussed herein, particles within the air flow, such as water andoil droplets and vapor, will move to the outer portion of the air flowdue to the swirl flow created by the swirl tube 100. The water and oildroplets will enter into the inner cavity 521 of the collection chamber520 via openings 513. The system 500 may be used to remove undesiredparticles from an air flow as would be appreciated by one of ordinaryskill in the art having the benefit of this disclosure.

FIG. 12 shows components that may be used to remove collected fluid,oil, and other particles from the inner chamber 221 of the collectionhousing 220. The collection housing 520 includes a rotary valve, alsoreferred to as a star valve, that enables collected fluid, oil, andother particles to be removed from the inner chamber 221. The rotaryvalve may be replaced with other devices such as an airlock type deviceor check valve that ensures air is not pulled into the system reducingthe velocity of air at the swirl vanes.

FIG. 13 is a flow chart of a method 400 of the present disclosure. Themethod 400 includes providing a flow of fluid through a forward secantswirl tube, at 410. The method 400 includes moving heaving particleswithin the flow of fluid toward an outer diameter of the forward secantswirl tube via centripetal acceleration, at 420. The method 400 includesremoving at least a portion of the heavier particles form the flow offluid, at 430. The method 400 includes discharging the flow of fluidfrom the forward secant swirl tube, at 440.

Although this disclosure has been described in terms of certainpreferred embodiments, other embodiments that are apparent to those ofordinary skill in the art, including embodiments that do not provide allof the features and advantages set forth herein, are also within thescope of this disclosure. Accordingly, the scope of the presentdisclosure is defined only by reference to the appended claims andequivalents thereof.

What is claimed is:
 1. An apparatus comprising: a central hub having acenterline and a circular perimeter; an outer housing, the outer housingcomprising a circular wall that extends from an inlet edge to an outletedge; a plurality of vanes that extend from the central hub to the outerhousing, the plurality of vanes equally spaced around the circularperimeter of the central hub, each vane of the plurality of vanes havingan inlet transition portion connected to a discharge portion, the inlettransition portion having a top edge and the discharge portion having abottom edge; and wherein the top edge of the inlet transition portion ofeach vane of the plurality of vanes is offset from the centerline of thecentral hub and the top edge forms a forward secant line with respect tothe centerline of the central hub and a direction of spin induced by theplurality of vanes.
 2. The apparatus of claim 1, wherein the pluralityof vanes comprises five vanes.
 3. The apparatus of claim 1, wherein theplurality of vanes comprises six vanes.
 4. The apparatus of claim 1,wherein the discharge portion of each vane of the plurality of vanes hasa constant incline along a line normal to the centerline of the centralhub.
 5. The apparatus of claim 4, wherein the inlet transition portionof each vane of the plurality of vanes comprises an upper portion, amiddle portion, a lower portion, a first bend at a first interfacebetween the upper portion and the middle portion, and a final bend at asecond interface between the middle portion and the lower portion,wherein the lower portion of the inlet transition portion is connectedto the discharge portion.
 6. The apparatus of claim 5, wherein the upperportion, middle portion, and lower portion of each vane of the pluralityof vanes comprises a face, wherein the face of the upper portion of theinlet transition portion of each vane of the plurality of vanes isoriented at a first angle with respect to a plane along the outlet edgeof the outer housing, wherein the face of the middle portion of theinlet transition portion of each vane of the plurality of vanes isoriented at a second angle with respect to the plane along the outletedge of the outer housing, and wherein the face of the upper portion ofthe inlet transition portion of each vane of the plurality of vanes isoriented at a final angle with respect to the plane along the outletedge of the outer housing, the first angle being greater than the secondangle and the second angle being greater than the final angle.
 7. Theapparatus of claim 6, wherein apparatus is comprised of stainless steel.8. The apparatus of claim 7, wherein a direction of flow through theplurality of vanes is upwards with respect to gravity.
 9. The apparatusof claim 8, the central hub comprising a top surface, the top surfacecomprises a first face, a second face, and an interface between thefirst face and the second face, wherein the first face extends downwardtoward the plurality of vanes from the interface and wherein the secondface extends downward toward the plurality of vanes from the interface.10. A system comprising: a flow tube having an outer housing, an inlet,and an outlet; an inner housing positioned within the outer housing ofthe flow tube; a collection housing having an inner chamber; at leastone opening between the inner housing and the outer housing, the atleast one opening in communication with the inner chamber of thecollection housing; a swirl tube positioned between the inlet and theoutlet of the flow tube, wherein fluid flowing through the inlet of theflow tube passes through the swirl tube, the swirl tube comprises: acentral hub having a centerline and a circular perimeter; an outerhousing, the outer housing comprising a circular wall that extends froman inlet edge to an outlet edge; a plurality of vanes that extend fromthe central hub to the outer housing, the plurality of vanes equallyspaced around the circular perimeter of the central hub, each vane ofthe plurality of vanes having an inlet transition portion connected to adischarge portion, the inlet transition portion having a top edge andthe discharge portion having a bottom edge; wherein the top edge of theinlet transition portion of each vane of the plurality of vanes isoffset from the centerline of the central hub and the top edge forms aforward secant line with respect to the centerline of the central huband a direction of spin induced by the plurality of vanes; and whereinthe swirl tube causes heavier particles of the fluid flowing through theswirl tube to flow into the inner chamber of the collection housing viathe at least one opening and the remaining fluid flowing out the outletof the flow tube.
 11. The system of claim 10, wherein the heavierparticles comprises at least one of moisture, oil droplets, and vapor.12. The system of claim 10, wherein the discharge portion of each vaneof the plurality of vanes has a constant incline along a line normal tothe centerline of the central hub.
 13. The system of claim 12, whereinthe inlet transition portion of each vane of the plurality of vanescomprises an upper portion, a middle portion, a lower portion, a firstbend at a first interface between the upper portion and the middleportion, and a final bend at a second interface between the middleportion and the lower portion, wherein the lower portion of the inlettransition portion is connected to the discharge portion.
 14. The systemof claim 13, wherein the upper portion, middle portion, and lowerportion of each vane of the plurality of vanes comprises a face, whereinthe face of the upper portion of the inlet transition portion of eachvane of the plurality of vanes is oriented at a first angle with respectto a plane along the outlet edge of the outer housing, wherein the faceof the middle portion of the inlet transition portion of each vane ofthe plurality of vanes is oriented at a second angle with respect to theplane along the outlet edge of the outer housing, and wherein the faceof the lower portion of the inlet transition portion of each vane of theplurality of vanes is oriented at a final angle with respect to theplane along the outlet edge of the outer housing, the first angle beinggreater than the second angle and the second angle being greater thanthe final angle.
 15. The system of claim 14, wherein the plurality ofvanes comprises five vanes and the outer housing has an inner diameterof 12 inches.
 16. The system of claim 15, wherein the plurality of vanescomprises six vanes and the outer housing has an inner diameter of 24inches.
 17. A method comprising: providing a flow of fluid through aforward secant swirl tube; moving heavier particles within the flow offluid toward an outer diameter of the forward secant swirl tube viacentripetal acceleration; removing at least a portion of the heavierparticles from the flow of fluid; and discharging the flow of fluid fromthe forward secant swirl tube.
 18. The method of claim 17, wherein theheavier particles comprises at least one of moisture particles, oilparticles, and vapor.
 19. The method of claim 18, wherein the forwardsecant swirl tube comprises: a central hub having a centerline and acircular perimeter; an outer housing, the outer housing comprising acircular wall that extends from an inlet edge to an outlet edge; aplurality of vanes that extend from the central hub to the outerhousing, the plurality of vanes equally spaced around the circularperimeter of the central hub, each vane of the plurality of vanes havingan inlet transition portion connected to a discharge portion, the inlettransition portion having a top edge and the discharge portion having abottom edge; and wherein the top edge of the inlet transition portion ofeach vane of the plurality of vanes is offset from the centerline of thecentral hub and the top edge forms a forward secant line with respect tothe centerline of the central hub and a direction of spin induced by theplurality of vanes.
 20. The method of claim 19, wherein the inlettransition portion of each vane of the plurality of vanes comprises aplurality of faces formed by a press brake.